Method and apparatus for erecting tower with hydraulic cylinders

ABSTRACT

A method and apparatus for constructing a tower, where the apparatus may include a structure including a foundation including a plurality of hydraulic cylinders; a truss tower located on the foundation and configured to support a tower built on the foundation; and a controller configured to control extension and retraction of the hydraulic cylinders.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to and is a continuation of U.S. patentapplication Ser. No. 14/317,343, filed Jun. 27, 2014. This applicationis incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present subject matter relates generally to tower structures, andmore specifically to methods and apparatus for assembling towerstructures.

BACKGROUND OF THE INVENTION

Construction of towers for support of various items has been practicedfor many years. Various towers of various materials, including wooden,steel, and, more recently, concrete, have been provided to support, forexample, electrical transmission lines. In a like manner, wind drivenapparatus including windmills and wind-driven power generators invarious forms and designed for many purposes (including for examplepumping of water from wells as well as, more recently, generation ofelectrical power) have also been developed.

Such towers are generally constructed of multiple pieces that areassembled at the location of the tower. The pieces are usually hoistedin place by a crane. Cranes can be very expensive to maintain andoperate, and a substantial hourly cost is incurred for every hour thecrane is on site.

For example, a large construction crane may require 16 truckloads totransport all of the component parts, substantial labor to assemble andinspect, and then substantial labor to disassemble. Accordingly, amethod and apparatus for constructing a tower that minimizes oreliminates the need for a crane is desired.

SUMMARY OF THE INVENTION

The present invention broadly comprises a method and apparatus forconstructing a tower. In one embodiment, the apparatus may include astructure including a foundation including a plurality of hydrauliccylinders; a truss tower located on the foundation and configured tosupport a tower built on the foundation; and a controller configured tocontrol extension and retraction of the hydraulic cylinders.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present subject matter, includingthe best mode thereof, directed to one of ordinary skill in the art, isset forth in the specification, which makes reference to the appendedfigures, in which:

FIG. 1 illustrates a perspective view of an embodiment of the presentinvention;

FIG. 2 is a top view of the foundation of the embodiment shown in FIG.1;

FIG. 3 illustrates a top view of the tower and a schematic of thecylinder control system;

FIG. 4 is a side view of all of the cylinders extended before theinsertion of a new level;

FIG. 5 is a side view showing half of the cylinders retracted and halfextended;

FIG. 6 is a side view of the first block that is fully inserted and thehydraulic cylinders below are extended to contact the block;

FIG. 7 is a side view of the insertion of the second block;

FIG. 8 is a side view of the completion of a level; and

FIG. 9 is a top view of an embodiment of the restraining truss shown inFIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference is presently made in detail to exemplary embodiments of thepresent subject matter, one or more examples of which are illustrated inor represented by the drawings. Each example is provided by way ofexplanation of the present subject matter, not limitation of the presentsubject matter. In fact, it will be apparent to those skilled in the artthat various modifications and variations can be made in the presentsubject matter without departing from the scope or spirit of the presentsubject matter. For instance, features illustrated or described as partof one embodiment can be used with another embodiment to yield a stillfurther embodiment. Thus, it is intended that the present subject mattercovers such modifications and variations as come within the scope of thedisclosure and equivalents thereof.

FIG. 1 shows a perspective view of an exemplary embodiment of anapparatus 10 for constructing a tower 80 in accordance with the presentinvention. Tower 80 supports wind turbine 82, but towers made accordingto the present invention may support other equipment, power lines, orother objects. Any such towers may be constructed according to thepresent invention.

Apparatus 10 includes a foundation 20 and a truss tower 40 located onthe foundation 20. Foundation 20 includes a plurality of hydrauliccylinders 22, shown in FIGS. 3-8. Truss tower includes vertical legs 42,upper restraining truss 44, and lower restraining truss 46. As shown inFIG. 2, the base 42A of each vertical leg 42 of the truss tower 40 restson foundation 20.

FIG. 1 shows a truss tower including two restraining trusses, but morethan two can be included and are within the scope of the presentinvention. The restraining trusses 44 and 46 provide horizontal force tosupport the tower 80 during construction of the tower. In particular,the restraining trusses 44 and 46 counteract uneven forces on the tower80 during the method of construction described hereafter.

FIG. 9 shows a close up top view of a restraining truss, such as upperrestraining truss 44. Each restraining truss includes force bearingdevices 48 to transfer force from the truss tower 40 to the tower 80.Further, the force bearing devices 48 allow tower 80 to move pastvertically as additional levels are added to tower 80 from below. In theembodiment shown in FIG. 9, the force bearing device includes rollers 49to exert horizontal force on tower 80 while still allowing tower 80 tomove vertically. However, other devices known in the art may be used inthis manner. Further, the force bearing devices may include hydrauliccylinders 50 to tighten the force bearing device up to the wall of tower80. The embodiment shown in FIG. 9 includes a hydraulic cylinder 50 foreach force bearing device 48. However, fewer may be used as long as therestraining truss can be sufficiently tightened around tower 80.

In the embodiment shown in FIGS. 1-9, tower 80 has an octagonalcross-section. However, other cross-section shapes are possible, such assquare or circular cross-sections. All of these modifications are withinthe scope of the invention.

Tower 80 as shown in FIG. 1 includes a wind turbine 82 located on top oflevels 84. In one embodiment, levels 84 are first constructed with acrane, the truss tower 40 is constructed around the levels 84, and thenthe crane lifts the wind turbine 82 to the top of levels 84. Thefollowing procedure is then used to add additional levels to the towerusing hydraulic cylinders 22. However, if a heavy object like a windturbine is not going to be located at the top of the tower, then thetruss tower 40 can be constructed over foundation 20 and all levels canbe constructed using the hydraulic cylinders 22. This would allow theelimination of the need for a crane, as the addition of levels using thehydraulic cylinders 22 only needs a forklift, as discussed hereafter.

In an embodiment for a tower 80 with a wind turbine 82, 10 2 m levels 82may be constructed using a crane, and a height of wind turbine 82 may be50 m. Thus, each leg 42 would be 20 m tall, upper restraining truss 44would be at 20 m in height while lower restraining truss 46 may be atapproximately 8 m from the bottom of truss legs 42. Truss legs 42 may besquare of 12 inches on a side, and may be 22 feet apart from each other.

In the embodiment shown in FIG. 1, foundation 20 is constructed, andhydraulic cylinders 22 and block supports 24 are installed in thefoundation 20. Hydraulic cylinders 22 are arranged in pairs, with ablock support 24 extending between each pair of cylinders. A pluralityof levels 84 are constructed using a crane, the truss tower 40 isconstructed around levels 82 and on foundation 20, and the wind turbine82 is added to the top of levels 84. Additional levels are then addedusing hydraulic cylinders 22 and block supports 24 as shown in FIGS.4-8. In the embodiment shown in FIGS. 1-9, hydraulic cylinders 22 andblock supports 24 are then removed from foundation 20 after the desirednumber of additional levels are added.

In the embodiment shown in FIGS. 1-9, there are 24 hydraulic cylinders22. In one embodiment, cylinders 22 are sized to lift a concrete towerwith a final weight of 1800 tons. However, towers of any dimensions andmaterial may be constructed using this method and apparatus. The sizeand number of cylinders may vary depending on the dimensions of thetower and the building material. All of these modifications are withinthe scope of the present invention.

In this regard, in the embodiment shown in FIGS. 1-9, each level 84 and86 is slightly wider than the level above, as shown in FIG. 3. When thefinal level is added, the bottom of this final level will line up withthe top of foundation 20.

The first step of the process is shown in FIG. 4, in which all ofhydraulic cylinders 22 are extended to push up tower 80 by the height ofone level. In the embodiment shown in FIGS. 1-9, all of the levels 84and 86 have approximately a same height. However, different heightscould be used as long as the extension height of hydraulic cylinders 22is greater than the tallest level. At this step, the tower must slidepast the force bearing devices 48 on the restraining trusses, as notedabove.

As shown in FIG. 5, one half of hydraulic cylinders 22 are thenretracted to allow block 86A of new level 86 to be inserted. As notedabove, in the embodiment shown in FIGS. 1-9, new level 86 is made of twoequal sized blocks 86A and 86B. However, embodiments where three or moreblocks are used and/or each block is more or less than half of eachlevel are possible and are within the scope of the present invention.

Block 86A is inserted by the use of a forklift. Block 86A is thenconnected to the level above. Block 86A may be adhered to the blockabove, or may have grooves or projections that mate with the blockabove, or both. During this time, uneven forces are placed on theexisting tower 80. Accordingly, restraining trusses 44 and 46 exerthorizontal forces on the tower 80 to prevent tower 80 from tipping overdue to these uneven forces.

At this point, the other half of the hydraulic cylinders 22 areretracted, as shown in FIG. 6. This allows block 86B to be insertedusing a forklift, as shown in FIG. 7. Block 86B is then connected to thelevel above in a similar manner as block 86A, as shown in FIG. 8. Thisshould end the uneven forces on the tower, and reduce the load on thetruss tower 40.

Finally, the new level 86 is pushed up the height of a level byextending all of the hydraulic cylinders 22, as shown in FIG. 4. Half ofthe hydraulic cylinders are then retracted to allow the next level to beadded, as described above. However, in the embodiment shown in FIGS.1-9, the seams between the two blocks are alternated from level tolevel. That is, the seam between two blocks is only located on aparticular face for every other level, as shown in FIG. 1. Thus, forexample, a first level 86 is constructed by lowering a front half ofhydraulic cylinders 22, adding block 86A to the front opening, loweringthe back half of hydraulic cylinders 22, and then adding back block 86B.The following level would be constructed by lowering either the right(or left) half of hydraulic cylinders 22, adding block 86A to the right(or left) opening, lowering the left (or right) half of hydrauliccylinders 22, adding block 86B to the left (or right) opening. This isaccomplished using the control computer 60 shown in FIG. 3.

Control computer 60 receives position and pressure readings from each ofthe cylinders 22 through lines 60A (FIG. 3 does not show all of lines60A). Control computer 60 then sends signals to control pressurizedfluid to each cylinder 22 through line 60C to pressure manifold 62.Based on the signals from the control computer 60, pressure manifold 62supplies pressurized fluid to each cylinder 22 through a respectivevalve 62A. (Not all of valves 62A are shown in FIG. 3.) Control computer60 also controls a return valve on each cylinder 22 through line 60B.(Not all of lines 60B are shown in FIG. 3.) When the return valve isopened by control computer 60, fluid runs through a respective returnline 66A to fluid reservoir 66. (Only one of the 24 return lines 66A isshown in FIG. 3). Fluid from fluid reservoir 66 is pressurized byelectrical or diesel pump 64 before it is supplied to the pressuremanifold 62.

Control computer 60 has several programs to control multiple sets of thecylinders 22. As discussed above, in the embodiment shown in FIGS. 4-8,half of cylinders 22 are controlled to extend and retract together, andthe halves are alternated for each level between (1) right and left halfand (2) front and back half. Thus, control computer 60 at has programsto extend and retract (1) the right half of cylinders 22, (2) the lefthalf of cylinders 22, (3) the front half of cylinders 22, and (4) theback half of cylinders 22. Additional commands such as all extend andall retract can also be programmed into control computer 60. Further, ifeach level includes more than 2 blocks, additional commands will beneeded to control smaller subsets of cylinders 22.

Accordingly, a tower 80 may be constructed with less use of a crane, orwithout the use of a crane at all. As a forklift is much cheaper tooperate than a crane, a substantial cost savings may be gained by usingthe present method and apparatus for constructing a tower.

The present written description uses examples to disclose the presentsubject matter, including the best mode, and also to enable any personskilled in the art to practice the present subject matter, includingmaking and using any devices or systems and performing any incorporatedand/or associated methods. While the present subject matter has beendescribed in detail with respect to specific embodiments thereof, itwill be appreciated that those skilled in the art, upon attaining anunderstanding of the foregoing may readily produce alterations to,variations of, and equivalents to such embodiments. Accordingly, thescope of the present disclosure is by way of example rather than by wayof limitation, and the subject disclosure does not preclude inclusion ofsuch modifications, variations and/or additions to the present subjectmatter as would be readily apparent to one of ordinary skill in the art.

The invention claimed is:
 1. An apparatus for constructing a tower, theapparatus comprising: a foundation including a plurality of hydrauliccylinders; a truss tower located on the foundation and configured tosupport a tower built on the foundation, the tower including a firsttower segment and a second tower segment; and a controller that controlsextension and retraction of the hydraulic cylinders to lift the firsttower segment, wherein when extended, the hydraulic cylinders directlyexert a vertical force on a bottommost surface of the first towersegment to move the first tower segment relative to the truss tower suchthat the second tower segment can be disposed below, and abut, thebottommost surface of the first tower segment.
 2. The apparatusaccording to claim 1, wherein the plurality of hydraulic cylinders arearranged in pairs.
 3. The apparatus according to claim 1, wherein thetruss tower includes at least two restraining trusses arranged aroundthe tower.
 4. The apparatus according to claim 3, wherein eachrestraining truss includes at least one force bearing device that exertsa horizontal force on the tower, wherein the at least one force bearingdevice includes a roller and a hydraulic cylinder, the roller beingconfigured to exert the horizontal force on the tower while allowing thetower to move vertically past the roller, and the hydraulic cylinderbeing configured to move the roller to contact the tower.
 5. Theapparatus according to claim 1, wherein the controller controls theplurality of hydraulic cylinders to all extend together, to retract asubset of the plurality of hydraulic cylinders, and to retract a rest ofthe plurality of hydraulic cylinders.
 6. The apparatus according toclaim 1, wherein the controller controls the plurality of hydrauliccylinders to all extend together, to retract one half of the pluralityof hydraulic cylinders, and to retract an other half of the plurality ofhydraulic cylinders.
 7. The apparatus according to claim 1, wherein theplurality of hydraulic cylinders are removable from the foundation aftercompletion of the tower.
 8. The apparatus according to claim 1, whereinthe tower moves with respect to the truss tower when the plurality ofhydraulic cylinders are extended, and the truss tower remains stationarywhen the plurality of hydraulic cylinders are extended.
 9. The apparatusaccording to claim 1, wherein the tower includes at least one wall andthe hydraulic cylinders directly exert a vertical force on a bottommostsurface of the wall portion of the tower to move the tower relative tothe truss tower.
 10. The apparatus according to claim 1, wherein thetower comprises concrete.